Q: My car has a rough idle and water leaking from the tailpipe - 1999 Toyota Land Cruiser

asked by on November 07, 2016

213k miles. Experiencing rough idle (needle steady but big vibration in every gear/felt at every stop), water steadily running out of tailpipe, and a little bit of white smoke out tailpipe, though it doesn't smell sweet, just like gas. First noticed the latter when I had it backed up to garage and within a minute the smell was so strong in there I had to move it.

Additionally, water is dripping from exhaust underneath car, with bit of smoke/steam leaking around boot.

-No milky substance in radiator or oil. -The coolant reservoir was low, but I just bought this and was the first time I had checked it. The radiator was still full of coolant. -Spark plugs don't look that bad. No gunk/build-up. No signs of any coolant anywhere. Changing them today though. -Cleaned the MAF -Cleaned the throttle body. -CEL came on but after battery disconnect, hasn't come back

Seems responsive and drives fine, but noticeablly struggles to maintain speed on long uphill grade. 55mph but have it floored.

Spark Plugs Replacement $113.11 - $716.47 Get a Quote
Fuel Injector Replacement $400.56 - $3968.30 Get a Quote
Car idle is rough Inspection $94.99 - $114.99 Get a Quote

Hello and thank you for contacting YourMechanic. If the smoke is slightly white, it could be burning the fuel too cold. This is an issue with a cylinder misfiring and causing raw fuel to enter the exhaust pipe. Check all of the cylinders for air, spark, and fuel. Make sure that all of the spark plugs are having a solid blue spark and that there are no burn spots on them. Check all of the injectors by unplugging one at a time from the harness to see if the engine idles even rougher.

If it does, then that injector was working. If it does not, then it is a possibility that the injector was not working. If everything checks out to be good, then you would need to do a compression test to see if there is a cylinder that has a low compression. This can be caused by a burned valve, a bent valve, burned or stuck rings, or a burned head gasket.

If you need further assistance diagnosing your engine, then seek out a professional mechanic, such as one from YourMechanic, who can come to your location to inspect the rough idle issue.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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